The broad concept of a knife and sheath provided with a mechanism for releasably retaining the knife in the sheath and for quickly releasing the knife from the sheath is known in the art. Specific embodiments of the concept are found in U.S. Pat. No. 2,391,574 issued Dec. 25, 1945 to G. E. Housinger and entitled DEVICE FOR LOCKING HUNTING KNIVES IN THEIR SCABBARDS, U.S. Pat. No. 2,527,710 issued Oct. 31, 1950 to Harold O. Davidson, Jr. and entitled DEVICE FOR LOCKING KNIVES IN THEIR SCABBARDS, U.S. Pat. No. 2,783,536 issued Mar. 5, 1957 to M. F. McQueary and entitled KNIFE AND SHEATH WITH LATCH MEANS, U.S. Pat. No. 2,439,197 issued Apr. 6, 1948 to Garrett J. Wykoff and entitled SHEATHED KNIFE FASTENING, U.S. Pat. No. 2,398,764 issued Apr. 23, 1946 to Donald C. Bailey and entitled SHEATHED KNIFE CLASP.
U.S. Pat. No. 2,783,536 to McQueary discloses a spring pressed latch mechanism wherein the sheath extends upwardly beyond the juncture of the handle and blade of the knife and one side of the sheath has a pin extending outwardly and engageable with a recess in the handle and the other side of the sheath has a metal spring bearing against the handle and urging it toward the retaining pin.
U.S. Pat. No. 2,391,574 to Housinger discloses a rigid scabbard extending completely about the blade of the knife with a portion of the scabbard extending into overlapping relation with a collar extending about the inner end of the handle. A flexible spring arm 10 is fastened to the portion of the blade within the handle, from which it extends outwardly and downwardly terminating in an outwardly projecting pin 13 receivable within a notch 14 in the scabbard.
The disclosures of McQueary and Housinger are typical of the teaching of the prior art known to applicant in the use of spring pressure urging the knife into frictional or locking engagement with its sheath. Such arrangements are objectionable in several respects. They do not positively lock the knife to the sheath in the sense that once the spring pressure is overcome the knife may be easily withdrawn in a single motion axially of its sheath or scabbard. This is desirable in some instances but in other instances it may be dangerously unsafe. Another objection is that the tip of the blade must be moved completely beyond the open end of the sheath in order to remove the knife from the sheaths of the prior art. This can be a time-consuming and awkward maneuver. These objections are overcome by the present invention which also offers other advantages.